If'n it's the mouse wheel that's the problem,you can map keys for 'next' and 'previous' but then you still have to scroll or page through the fixed order.If'n it's the scrolling that's the problem, no.

I'm using Windows 7 and don't have a slow mouse wheel, they scroll as fast as I can turn the wheel.

I've asked about this before, and apparently the issue lies with how the game transfers inputs during netgames and recording replays, so accommodating keybinds to individual weapons would require a massive rewrite of the networking code.

Personally, I'd just simulate several Prev/NextWeapon inputs instead depending on the position between your selected weapon and currently equipped weapon. So for example, if I'm currently holding a Fusion Pistol (which I suppose is the fourth entry in your list of weapons) and wanted to switch to my fists (which is the first entry) which I bound to the Q key, pressing that key would simulate three PrevWeapon inputs since that's the amount it takes to get from the Fusion Pistol to your fists. Or if I had a SPNKR equipped (which I guess is the seventh entry) and wanted to switch to my fists, it'd simulate one NextWeapon input as opposed to six PrevWeapon inputs which could increase weapon switching time more than necessary and because reaching the end of the weapon lists automatically boots you back to the first entry anyways.

I have no idea how feasible this idea is, but who knows if it could work with Aleph One's code.